MILLWALL boss Neil Harris revealed he had a “conundrum” at half-time in their Championship clash with Sheffield United – before deciding for a rare change of system to 3-5-2.

The Lions had started brightly against the Blades and deservedly went in front through Lee Gregory, but David Brooks equalised for the improving visitors before the break.

Chris Wilder’s side were briefly on top at the start of the second half, before Millwall settled in their new system and Mahlon Romeo, now playing right wing-back, put his side back in front from Gregory's superb pass. Jake Cooper scored a third with two minutes left to seal an emphatic win.

“I thought leading up to the first goal we were excellent and then for whatever reason we stepped off a little bit, we couldn’t get the press right, we couldn’t get near the ball,” Harris said. “They showed exactly why they’re in the top three in the division on the back of the 20 minutes leading up to half-time, and I thought quite rightly they got back onto level terms.

“We had a conundrum at half-time, my staff and I: do we leave it as it is and hope that we get a foothold back in the game and our 4-4-2 dictates play? Or we can change it.

“We made a brave decision, we changed to 3-5-2 to match them up at half-time and you’ve got a 10-minute team-talk to do it, to try to get messages to the players. Then you put them out there and say, ‘right, you have to learn yourselves, you have to learn quickly and adjust what you do’.

“I thought they were outstanding. They’re never going to let me down on effort, determination, desire to play for this club, never going to shirk a challenge on or off the pitch. Today there were some real moments of quality as well.

“If we want an epitome of what this club is all about then that second goal does it in one go. Lee Gregory has tracked back, put in an aggressive tackle and then the forward pass, the run from Mahlon and the quality to finish from a player that has had to wait 18, 19 games for his opportunity. That epitomises my squad.”

Gregory’s goal was his third of the season, and Harris was delighted with the striker’s performance.

He said: “I thought Lee was excellent, I thought he played the same as he has in the last nine or 10 games but today he had the goal and an assist to go with it. He deserved that.

“His mentality every day, his attitude every day in training, the positions he has got in have been everything you would want apart from that end product.

“I took him off because he was ill, he was sick before the game and sick at half-time. But he wanted to play because it was against his hometown club. And he got his reward by having a big heart.”

Blades boss Wilder said: "I've co complaints with the result, my complaints are about my team. We haven't done enough to win the game, they have."